1. Field of the Invention
The present invention relates to a spring mechanism for fixing a compressed coil spring to contact a dry cell, for example, and a cell contact mechanism for small electronic devices.
2. Description of the Related Art
Conventionally, in a cell housing of an electronic device, for example, a spring mechanism is used as a terminal plate to contact the cathode side of the cell. In the spring mechanism, a claw for fixing the compressed coil spring constituting the spring mechanism is formed at a predetermined position on the terminal plate in the cell housing.
The spring mechanism is formed as described in Jpn. Pat. Appln. KOKAI Publication No. 6-313456, for example. A pair of U-shaped tangential lines is cut in a process of punching a metallic cathode terminal member. The portion surrounded by the U-shaped tangential lines is raised. The raised portion is bent in a required direction to form a pair of bent fixing lugs in the terminal member. Then, a wire ring at the base end of a coil spring is brought into contact with the terminal member, so that both sides of the wire ring are opposed to the bent inside surfaces of the bent fixing lugs. The bent lugs are turned down toward both sides of the wire ring in this state, thereby fixing the coil spring to the terminal member.
However, in the art described in the Jpn. Pat. Appln. KOKAI Publication No. 6-313456, the coil spring is fixed to the terminal member in two steps. That is, the wire ring at the base end of the coil spring is brought into contact with the terminal member, so that both sides of the wire ring are opposed to the bent inside surfaces of the bent fixing lugs, and the bent lugs are turned down, or bent toward both sides of the wire ring, as a post-step in the coil spring fixing process.
Further, in the art of the Jpn. Pat. Appln. KOKAI Publication No. 6-313456, since the bent fixing lugs are fixed by bending toward both sides of the wire ring, once the coil spring is fixed, the coil spring cannot be removed without bending back the bent lugs to the original position.